Numbering-head



M. H. KERN.

NUMBERING HEAD. APPLICATION FILED NOV. 6, 1920.

1,385,835. Patented m 26, 1921.

, Invehtor:

/& Atty,

UNITED STATES PATENT OFFICE.

MAXIMILIAN H. KERN, 03: NE?! YQRK, N. Y., ASSIGNOR 'I'O ROBERTS IIUMBERING MACHINE CGMEANY,

[i I GJRPOBATI035T OF NEW YORK.

lTUIiIBERING-HEAD.

Specification of Letters Patent.

Patented July 26*, 1921,

To all whom it may 0012 ccra:

Be it known that I, MAXIMILIAN H. KERN, a citizen of the United States, residing at Ridgewood, in the borough of Queens, city of New York, county of Queens, and State of New York, have invented certain new and useful Improvements in Numbering- Heads, of which the following is a specification, reference being had therein to the accompanying drawings, which form a part thereof.

My invention relates to numbering heads, and more particularly to the detent pawl structure of such heads, which structure is applicable to either automatic of non-auto matic wheel printing machines.

In numbering heads and other types of wheel printing machines, a plurality of rotatably mounted wheels having printing characters or types upon the periphery thereof are employed, such wheels being progressively and automatically rotated with the actuation of the machine in some types of heads, and being hand-operated in other types of heads.

The printing surfaces of the various wheels are inked between impressions in different manners according to the structure of the machine as determined by its particular character of use.

, These characteristics of the machine are old and well known in this art, my invention relating more particularly to the particular construction of the detent pawl mech anism by which the springs acting upon the pawl associated with each wheel, will have a tensioning pressure applied thereto which will be uniform with the tensioning pressure applied to the pawls of all other wheels, and whereby the vibration resulting from the actuation of the mechanism will have no tendency to break the detent pawl springs or cause a variance in the tension thereof which will tend to permit one of the wheels to rotate more freely than other wheels, with a resultant likelihood of rotary movement of one wheel being imparted to the adjoining wheels through the frictional engagement of said wheels, or the presence of congealed or dried ink between adjacent wheels.

In addition to having the above characteristic of maintaining a substantially constant uniform tension in the detent pawl springs, a numbering head made in accordance with my invention may be quickly and accurately assembled or disassembled, and the number of parts entering into the machine may be reduced.

The invention consists primarily in a numbering head embodying therein a frame, a plurality of printing wheels rotatably mounted in said frame, each of said wheels having a ratchet wheel rotatable therewith, a detent pawl cooperating with each ratchet wheel, a spring having one end thereof supported. upon said frame and the other end thereof engaging a pawl, and means cooperating with said frame and applying a constant tensioning pressure to said spring intermediate said point of support and said polnt of engagement thereof with the pawl; and in such other novel features of construction and combination of parts as are here inafter set forth and described, and more particularly pointed out in the claims here to appended.

Referring to the drawings,

Figure 1 is a rear view of a numbering head embodying my invention; Y

Fig. 2 is a section thereof on the line 2-2 of Fig. 1; and

Fig. 3 is a detail isometric view of the form of the pawl detent springs shown in Fig. 1. Y

Like letters refer to like parts throughout the several views.

In the accompanying drawings, I have shown my invention as applied to the head of a hand-operated numbering machine, although it is apparent that it is equally applicable to numbering heads to be applied to power operated machines, or to machines in which the various printing wheels are manually operative instead of being automatically actuated as in the two types of wheels above referred to; All types of wheel printing machines have certain characteristics in common which are exemplified in the machine shown in the drawings.

In the form of the invention shown in the drawings, I employ a yoke frame at having therein a fixed shaft 7) upon which a plurality of wheels 0, cl, 6, f, g and h are r0- tatably mounted. Each printing wheel 0 to 72. carries a ratchet wheel 0, d, e, f, g and h secured thereto or otherwise associated therewith, so as to control the rotary movement of said wheel in one direction through the spring pressed pawls 0?; e1, 6 fig? and I 72? associated therewith respectively. Said pawls also serve to insure accurate alinement of the characters on said wheels which are in the printing position. a

In the form of the invention shown, I employ a ratchet wheel 2' having associated therewith a pawl i, the function of said ratchet wheel being to permit the setting of the head in a manner to cause a repetition of the printing of a definite number, a construction known in the art as a repeat mechanism.

In the form of the invention shown, the digit wheels 0 to h are progressively and automatically actuated by means of a swing frame 7' carrying a sequence of graduated pawls is, spring pressed in the usual manner into engagement with the various ratchet wheels 0 to h, each of said wheels being provided with a recess such as that shown at Z. Fig. 2, for permitting said pawl to progressively engage the ratchet teeth of succeeding wheels.

The construction heretofore described is old and well known in this art, and no claim of invention ismade thereto, my present invention relating more particularly to the manner of applying spring pressure, to the various pawls c to h and to the pawl z" cooperating with the repeat wheel a when such wheel is used in the mechanism of the head, although such is nonessential, and is employed only in some types of hand-operated automatic machines.

Heretofore in this art, the detent pawls have been pressed into engagement with their cooperating ratchet wheels by various types of springs. Wire springs have been employed secured by means of acoil section upon. the shaft upon which the pawls are pivoted, and there have also been used comb springs secured to the yoke in which the printing wheels are mounted, by means of a plurality of screws.

In the former construction the labor of assembling the pawls of the machine is somewhat great, while in the latter type of machine there is a tendency of the head of the comb'sp-ring to bow slightly between the points of the application-of the screws and thus, cause the development of an unequal tensioning pressure upon different pawls;

There is also likelihoodlof said screws becoming loosened as a result of vibration, with a resultant lossof tension in the spring and increased likelihood of a failure of the printing wheelsto work properly.

In a numbering head made in accordance with my invention, I employ a spring m of the comb type, the ,teeth of which adjacent the free ends are adapted to bear upon the respective pawls and the head of which is adapted to be supported in a fixed relation to the topof the yoke a. i

I This spring is tensioned through the me dium of a member rigidly supported with relation to said yoke and applying a tensioning pressure to said spring intermedi-. ate the point of support thereof upon the yoke, and of the engagement of the several teeth with their cooperating pawls. In this manner, I am not only enabled to accurately position each spring tooth with relation to its pawl, but apply and maintain a uniform tensioning stress throughout the entirebreadth of-the comb spring, and thus insure the development of substantially the same tension in each tooth with a resultant uniformity in the pressure exerted by each pawl upon its cooperating ratchet.

In the drawings I have shown the spring at as having a sequence of teeth m, m m 922*, m and m associated with the pawls c to h respectively, and a tooth m associated with the pawl 2". The head a of this comb spring m is formed to provide a trans verse-pocket or trough a adapted to receive the edge of the top bar of the frame a, and a second pocket or trough M, the mouth of which is presented in the reverse direction, the loop of metal forming said pocket n having its edges in close proximity to'the arms of the yoke a. The side of said pocket 72 adjacent the teeth an to m is deeper than that adjacent the pocket at, so as-to offset said teeth in relation to said pocket at, or to the top of the yoke a. l

The various spring teeth 9% to m are tensioned by means of a pin 0 passing through openings in the arms of the frame a and through the pocket a and engaging the bottom of said pocket, it being necessary to tension the various springs by'applying a pressure thereto toward the yoke a in order to permit the insertion of said pin ,0, after which a constant tension of the springs will be maintained by said pin which will engage every point of the head of the comb spring and thus insure uniformity in the tensioning pressure upon said springs.

In assembling a head made in accordance with my invention, after the wheels and the other mechanisms associated therewith have been mounted in the yoke a,'and the various pawls properly mounted andengaged each with its cooperating ratchet wheel, the po'cket'or trough n of the spring plate m is placed with its walls astride the edge of the top of the yoke a, thus bringing the side edges of the trough n between the arms of said yoke and accurately positioning each of the teeth m to m" with relation 7 When the spring is in this position, a tensioning pressure is applied thereto intermediate the point of engagement of the trou 'hed portion a with the yoke a and of the several teeth with their cooperating pawls. This forces the troughed portion a inwardly of the yoke so as to permit the pin 0 to be inserted in the opening in the arms of said yoke and passed lengthwise through said troughed portion n When the pin is properly positioned, the tensioning pressure is relieved, the tension thus developed in the teeth m to m forcing the bottom of the troughed portion a into engagement with said pin, the reflex action of said teeth being very slight, so that the engagement of the bottom of the trough with the pin will maintain all of said teeth under tension. Since the entire spring a flexes as a whole, and since the pin 0 is en gaged with the bottom of the trough throughout the entire length thereof, it is apparent that there will be uniform tension upon all of the teeth which will be constant since there can be no displacement of the pin 0 and no tendency of said spring to how by reason of the transverse rigidity imparted thereto by the troughed portion a and 40 It will be observed that in assembling the head, all of the springs cooperating with the various pawls are simultaneously applied to the head and are held in position before said springs are placed under tension.

The insertion of the pin 0 does not require any drilling and tapping of the yoke a. Said pin, when the spring has been properly tensioned by means of a suitable tool or jig, may be quickly assembled in the machine, or as quickly removed therefrom when it is desired to disassemble the head.

When a spring construction such as is herein described, is employed, all of the spring teeth will be simultaneously and uniformly tensioned and no such loss of adjustment of parts can occur while the machine is in use, as to prevent loss oftension of the springs. The manner of mounting the spring permits the use of fairly heavy springs, thus imparting a greater factor of safety in the operation of the head and insuring a more accurate alinement of the characters in the printing position, since in the event of slight overrunning of any wheel, the detent pawls are relied upon-to return any wheel to its proper alined position.

It is apparent that the construction herein described is applicable to various different types of numbering heads, either hand or machine operated, and that various modifications in the construction of the spring plate on and in the manner of maintaining the tension of this plate through the medium of a pin engaging the spring plate throughout the entire width thereof, may be e1nployed, varying with changes of design of the head structure proper.

It is therefore not my intention to limit the invention to the precise details of construction shown in the drawings, it being apparent that such may be varied without departing from the spirit and scope of the invention.

Having described the invention, what I claim as new and desire to have protected by Letters Patent, is r 1. A numbering head embodying therein a frame, a plurality of printing wheels rotatably mounted in said frame, each of said wheels having a ratchet wheel rotatable therewith, a detent pawl cooperating with each ratchet wheel, a spring having one end thereof supported upon said frame and the other end thereof engaging a pawl, and means cooperating with said frame and applying a constant tensioning pressure to said spring intermediate said point of support and said point of engagement thereof with the pawl.

2. A numbering head embodying therein a yoke frame, a plurality of printing wheels rotatably mounted therein, a ratchet wheel carried by and rotatable with each printing wheel, a detent pawl cooperating with each ratchet wheel, a comb spring each tooth of which cooperates with a detent pawl, the free edge of the head of said comb spring being formed to engage the edge of the cross bar of said yoke frame, and other portions thereof being adapted to engage the arms of said frame, and means cooperating with said frame and applying a constant tensioning pressure to said spring intermediate said point of support and said point of engage ment thereof with the pawl.

3. A numbering head embodying therein a yoke frame, a plurality of printing wheels rotatably mounted herein, a ratchet wheel carried by and rotatable with each printing wheel, a detent pawl cooperating with each ratchet wheel, a comb spring each-tooth of which cooperates with a detent. pawl, the free edge of the head of said comb spring being formed to engage the edge of the cross bar of said yoke frame, and other portions thereof being adapted to engage the arms of said frame, and a member removably mounted in said yoke frame and adapted to engage said spring throughout its entire width intermediate said formed portion of the head engaging the frame and the points of engagement of the several teeth with their respective detent pawls, whereby a constant uniform tensioning pressure is applied to all of said teeth.

at. A numbering head embodying therein a yoke frame, a plurality of printing wheels rotatably mounted therein, a ratchet wheel carried by and rotatable with each printing wheel, a detent pawl cooperating with each ratchet wheel, a comb spring each tooth of which cooperates with a detent pawl, the head of said spring having a transverse pocket adapted to receive the cross bar of the yoke frame and a. relatively deeper pocket opening outwardly of said frame, the loop of metal forming said pocket having its side edges in close proximity to the sides of said frame and being positioned adjacent the several teeth, and a pin passing through openings in the sides of said frame, and said last named pocket in continuous engagement with the bottom thereof, whereby acontinuousy uniform tensioning pressure is applied to all of said teeth.

- In witness whereoi I have hereunto a1- fixed my signature, in the presence of two subscribing Witnesses, this 24th day of September, 1920.

MAXI ILIANH. Kenn Witnesses: 7

F. T. WENTWORTH, FRIEDA KOEHLER. 

